Tool assemblies with a gap locking member

ABSTRACT

A tool assembly includes an anvil and a cartridge assembly movable from an open position to a closed position, and a locking member movably supported on a distal portion of the cartridge assembly. The locking member is configured to move into a slot of the anvil as the anvil and cartridge assembly move toward the closed position to set a gap distance between the anvil and cartridge assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional Application of U.S. patent application Ser. No. 16/789,746, filed on Feb. 13, 2020, which claims the benefit of and priority to U.S. Provisional Patent Application No. 62/817,807, filed on Mar. 13, 2019, the entire contents of each of which being incorporated by reference herein.

BACKGROUND 1. Technical Field

This disclosure is directed to a surgical stapling device and, more particularly, to a tool assembly of a surgical stapling device that defines a tissue gap and includes a locking member to maintain the tissue gap during firing of the tool assembly.

2. Background of Related Art

Surgical stapling devices are commonly used during a variety of surgical procedures to staple and/or cut tissue. Stapling and cutting of tissue can be accomplished more quickly using surgical stapling devices than can be accomplished using traditional suturing techniques. In addition, endoscopic stapling devices can be used to perform less invasive surgical procedures than possible using traditional suturing techniques. As such, the use of surgical stapling devices to perform certain surgical procedures to reduce patient trauma and improve patient recovery times is desirable.

Typically, linear endoscopic surgical stapling devices include a tool assembly that includes a staple cartridge and an anvil assembly that are movable in relation to each other between open and clamped positions. The staple cartridge defines a plurality of staple pockets that receive staples and the anvil assembly defines a plurality of staple deforming pockets. When the tool assembly is in the clamped position, the staple deforming pockets of the anvil assembly are aligned with the staple pockets of the staple cartridge such that legs of the staples are received and deformed within the staple deforming pockets when the stapling device is fired. The staple cartridge and the anvil assembly must be properly aligned to effect proper staple formation.

Generally, the staple cartridge and the anvil assembly have proximal ends that are secured to each other by a pivot member such that the staple cartridge and the anvil assembly can be pivoted from the open position in which distal ends of the staple cartridge and the anvil assembly are spaced from each other to the clamped position in which the staple cartridge and the anvil assembly are in juxtaposed alignment. During firing of the staples from the staple cartridge, forces on the staple cartridge and the anvil assembly for firing the staples tend to deflect the staple cartridge and anvil assembly outwardly away from each other. In certain stapling devices, a knife bar is provided that includes upper and lower beams that engage the anvil assembly and staple cartridge to minimize deflection of the anvil and cartridge assemblies during firing.

SUMMARY

One aspect of this disclosure is directed to a tool assembly including an anvil, a cartridge assembly, and a locking member. The anvil and the cartridge assembly each have a proximal portion and a distal portion. The proximal portion of the cartridge assembly is movably coupled to the proximal portion of the anvil. The distal portion of the anvil defines a first slot therein. The locking member is movably supported on the distal portion of the cartridge assembly. The locking member is configured for receipt in the first slot of the anvil to set a gap distance between the anvil and cartridge assembly when the anvil and cartridge assembly are in the closed position.

In aspects, the locking member may include a first latch arm configured for receipt in the first slot of the anvil when the anvil and cartridge assembly are in the closed position.

In aspects, the first latch arm may have an extension configured to be captured in the first slot of the anvil when the first latch arm distally translates.

In aspects, the locking member may include a second latch arm. The first and second latch arms may be disposed on opposite lateral sides of the cartridge assembly.

In aspects, the distal portion of the anvil may define a second slot therein configured for receipt of the second latch arm of the locking member.

In aspects, the first and second slots may be disposed on opposite lateral sides of the anvil.

In aspects, the tool assembly may further include a clamping member operably coupled to the proximal portion of each of the anvil and cartridge assembly and configured to move the anvil and cartridge assembly from an open position to a closed position. The locking member may be configured to be coupled to the clamping member, such that advancement of the clamping member moves the locking member into the first slot of the anvil to set a gap distance between the anvil and cartridge assembly.

In aspects, the locking member may include an elongate element and a first latch arm. The elongate element may have a proximal end portion configured to be coupled to the clamping member. The first latch arm may extend upwardly from a distal end portion of the elongate element. The first latch arm may be configured to translate distally into the first slot of the anvil in response to advancement of the clamping member.

In aspects, the clamping member may have a distally-extending latch member configured to couple to the proximal end portion of the elongate element of the locking member upon the anvil and cartridge assembly moving to the closed position.

In aspects, the latch member of the clamping member may have a protrusion, and the proximal end portion of the elongate element of the locking member may define an opening configured for removable receipt of the protrusion.

In aspects, the tool assembly may further include a sled slidably received in the cartridge assembly and configured to move from a proximal position to a distal position to advance staples from the cartridge assembly. The sled may be operably coupled to the clamping member, such that advancement of the sled from the proximal position toward the distal position distally translates the locking member.

In aspects, the tool assembly may further include an elongate plate slidably coupled to the cartridge assembly. The elongate plate may define a proximal slot in a proximal end portion of the elongate plate, and a distal slot in a distal end portion of the elongate plate. The clamping member may be received in the proximal slot and the locking member may be received in the distal slot.

In aspects, the locking member may be configured to lockingly engage the first slot in the anvil in response to advancement of the elongate plate by the clamping member.

In aspects, the locking member may be an I-beam having a bottom end portion received in the distal slot of the elongate plate, and a top end portion configured for receipt in the first slot of the anvil.

In aspects, the elongate plate may be configured to advance relative to the locking member a predetermined distance prior to engaging and advancing the locking member.

In aspects, the locking member may be pivotably supported by the distal portion of the cartridge assembly and configured to pivot into locking engagement with the slot as the anvil and cartridge assembly move toward the closed position.

In aspects, the tool assembly may further include a biasing member coupled to the locking member for resiliently biasing the locking member toward a locking position.

In aspects, the distal portion of the anvil may have a cam surface and a support ledge. The cam surface may be configured to pivot the locking member out of the locking position as the anvil and cartridge assembly move toward the closed position. The biasing member may be configured to pivot the locking member toward the locking position and onto the support ledge when the anvil and cartridge assembly enter the closed position.

In aspects, the locking member may include a top end portion including an extension configured to be supported on the support ledge of the anvil to prevent the anvil and cartridge assembly from moving out of the closed position. The locking member may include a bottom end portion pivotably supported in the cartridge assembly and coupled to the biasing member.

In another aspect of the disclosure, a tool assembly is provided and includes an anvil and a cartridge assembly each having a proximal portion and a distal portion. The proximal portion of the cartridge assembly is movably coupled to the proximal portion of the anvil. The distal portion of the anvil defines a slot therein. The tool assembly includes a clamping member and a locking member. The clamping member is operably coupled to the proximal portion of each of the anvil and cartridge assembly and configured to move the anvil and cartridge assembly from an open position to a closed position during a first advancement of the clamping member. The locking member is slidably supported on the distal portion of the cartridge assembly. The locking member is configured to be coupled to the clamping member upon the anvil and cartridge assembly moving to the closed position, such that a second advancement of the clamping member advances the locking member into locking engagement with the slot of the anvil to set a gap distance between the anvil and cartridge assembly.

As used herein, the terms parallel and perpendicular are understood to include relative configurations that are substantially parallel and substantially perpendicular up to about +or −10 degrees from true parallel and true perpendicular.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the disclosed linear surgical stapling device including a tool assembly are described herein below with reference to the drawings, wherein:

FIG. 1 is a side perspective view of an exemplary embodiment of the disclosed staple reload including a tool assembly in an open position;

FIG. 2 is an exploded perspective view of the tool assembly shown in FIG. 2 including a drive assembly;

FIG. 3A is a perspective view of a first side of components of the drive assembly of FIG. 2 illustrating first and second drive shafts of the drive assembly coupled to one another;

FIG. 3B is a perspective view of a second side of the components of the drive assembly of FIG. 3A;

FIG. 4 is a longitudinal cross-sectional view of the drive assembly of FIG. 3A illustrating a connector pin coupling the first and second firing shafts;

FIG. 5 is a longitudinal cross-sectional view of the drive assembly of FIG. 3A illustrating the connector pin disengaged from one of the firing shafts;

FIG. 6 is an enlarged perspective view of the tool assembly shown in FIG. 1 in the open position;

FIG. 7 is an enlarged perspective of the area of detail “7” indicated in FIG. 6;

FIG. 8 is an enlarged perspective of the area of detail “8” indicated in FIG. 6;

FIG. 9 is a perspective view of a channel and locking member of a cartridge assembly of the tool assembly shown in FIG. 2;

FIG. 10 is a perspective view of a clamping member and locking member of the cartridge assembly shown in FIG. 1 illustrated in a decoupled state;

FIG. 11 is a side perspective view of the tool assembly shown in FIG. 1 illustrating the locking member in a non-locking position;

FIG. 12 is an enlarged perspective view of the area of detail “12” shown in FIG. 11 illustrating the clamping member engaged to the locking member;

FIG. 13 is a top perspective view of the tool assembly of FIG. 1 illustrated in a closed position with the locking member shown in a locking position;

FIG. 14 is a bottom perspective view of the tool assembly of FIG. 13;

FIG. 15 is a longitudinal cross-sectional view of another exemplary embodiment of a tool assembly including a clamping member, an elongate locking plate, and a locking member;

FIG. 16 is a longitudinal cross-sectional view of the clamping member, the elongate locking plate, and the locking member shown in FIG. 15;

FIG. 17 is a perspective view of the locking member of FIG. 15;

FIG. 18 is a longitudinal cross-sectional view of the tool assembly of FIG. 15 illustrating the locking member in a non-locking position;

FIG. 19 is a longitudinal cross-sectional view of the clamping member, the elongate locking plate, and the locking member of FIG. 18 illustrating the elongate locking plate in an advanced position;

FIG. 20 is a longitudinal cross-sectional view of the tool assembly of FIG. 15 illustrating the clamping member, the elongate locking plate, and the locking member in a locking position;

FIG. 21 is a longitudinal cross-sectional view of the tool assembly of FIG. 15 illustrating the locking member in a retracted position;

FIG. 22 is a longitudinal cross-sectional view of the clamping member, the elongate locking plate, and the locking member of FIG. 21;

FIG. 23 is a longitudinal cross-sectional view of another exemplary embodiment of a tool assembly including a locking member illustrating the tool assembly shown in an open position;

FIG. 24 is longitudinal cross-sectional view of a distal end portion of the tool assembly of FIG. 23 with the tool assembly in a partially closed position and the locking member making an initial contact with an anvil;

FIG. 25 is a longitudinal cross-sectional view of the tool assembly of FIG. 23 with the tool assembly in a fully closed position and the locking member lockingly engaged to the anvil; and

FIG. 26 is a longitudinal cross-sectional view of the tool assembly of FIG. 23 illustrating the locking member disengaged from the anvil.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the disclosed tool assemblies will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. However, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure and the present tool assemblies may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure.

The present disclosure provides a tool assembly including a locking member movably supported in a cartridge assembly of the tool assembly. An anvil of the tool assembly defines a slot in a distal end portion of the anvil. The locking member is positioned for receipt in the slot of the anvil when the tool assembly is approximated about tissue a selected distance. The locking member is configured to selectively lock the anvil and cartridge assembly to maintain a gap distance between distal ends of the anvil and cartridge assembly before, during, and/or after staples are fired from the tool assembly.

In this description, the term “proximal” is used generally to refer to that portion of the device that is closer to a clinician, while the term “distal” is used generally to refer to that portion of the device that is farther from the clinician. In addition, the term “clinician” is used generally to refer to medical personnel including doctors, nurses, and support personnel.

In FIG. 1, a staple reload is illustrated generally as staple reload 10 and is configured to be coupled to a handle assembly (not shown) of a surgical stapling device, such, as for example, a linear or curved surgical stapling device. In aspects, the staple reload 10 may be incorporated into and actuated by a robotic surgical system. The staple reload 10 generally includes a proximal body portion 18 and a tool assembly 20. The tool assembly 20 is articulatable relative to the proximal body portion 18 from a position aligned with a longitudinal axis “X” defined by the proximal body portion 18 to a position misaligned with the longitudinal axis “X.” The tool assembly includes an anvil 34 and a cartridge assembly 36 pivotably coupled to the anvil 34.

With reference to FIGS. 2-5, the staple reload 10 also includes a drive assembly 22 that includes a first, resilient firing shaft 24 supporting a sled 26 and a second, resilient firing shaft 28 supporting a clamping member 30. The first and second firing shafts 24, 28 each have a proximal end portion 24 a, 28 a and a distal end portion 24 b, 28 b. The proximal end portion 24 a of the first firing shaft 24 is configured to be operably coupled to a drive rod 33 (FIG. 3B) for translating the first firing shaft 24 through the proximal body portion 18. The distal end portion 24 b of the first firing shaft 24 abuts, is formed with, or is otherwise coupled to the sled 26 for translating the sled 26 through the cartridge assembly 36. As known in the art, the first firing shaft 24 can be moved from a retracted position to an advanced position to advance the actuation sled 26 through the tool assembly 20 to sequentially eject staples into tissue clamped by the tool assembly 20.

The distal end portion 28 b of the second firing shaft 28 abuts, is formed with, or is otherwise coupled to the clamping member 30 for moving the clamping member 30 between proximal and distal positions for respectively opening and closing the tool assembly 20. The second firing shaft 28 may be fabricated from a pair of elongated laminates. In aspects, the second firing shaft 28 may be a monolithic structure. The clamping member 30 is configured to advance with the second firing shaft 24 the length of a slot 32 in the anvil 34 to close the tool assembly 20.

The proximal end portion 24 a, 28 a of each of the first and second firing shafts 24, 28 defines a pin hole 24 c, 28 c having received therein a connector pin 38 for detachably connecting the first and second firing shafts 24, 28 to one another. When the pin 38 is received in each hole 24 c, 28 c of the first and second firing shafts 24, 28 (FIGS. 3B and 4), advancement of the first firing shaft 24 drives a concomitant advancement of the second firing shaft 28. The pin 38 has a head 38 a received in longitudinally-extending cutout 40 defined in an inner surface of the proximal body portion 18. The head 38 a of the pin 38 is biased laterally into the cutout 40 and away from the first and second firing shafts 24, 28 by a biasing member 42 (e.g., a coil spring).

The cutout 40 has a proximal section 40 a, and a distal section 40 b recessed at a greater depth than the proximal section 40 a. As the first and second firing shafts 24, 28 move distally a predetermined distance, corresponding with a closing of the tool assembly 20 by the clamping member 30, the pin 38 moves from the proximal section 40 a of the cutout 40 toward the distal section 40 b of the cutout 40. Due to the bias exerted on the head 38 a of the pin 38 by the biasing member 42, the pin 38 is urged laterally into the distal section 40 b of the cutout 40 (FIG. 5), whereby a tail end 38 b of the pin 38 exits the hole 24 c in the first firing shaft 24. With the pin 38 no longer engaged to both the first and second firing shafts 24, 28, continued advancement of the first firing shaft 24 fails to result in further advancement of the second firing shaft 28. As such, the sled 26 (FIG. 2) of the drive assembly 22 may advance through the tool assembly 20 to eject staples into tissue while the clamping member 30 is maintained in a position proximal of the tissue-engaging surfaces of the anvil 34 and cartridge assembly 36.

FIGS. 1, 2, and 6 illustrate the tool assembly 20 which includes the anvil 34 and cartridge assembly 36 movably coupled to one another. Each of the anvil 34 and the cartridge assembly 36 includes a proximal portion 34 a, 36 a and a distal portion 34 b, 36 b. The proximal portion 34 a of the anvil 34 is coupled to the proximal portion 36 a of the cartridge assembly 36 such that the tool assembly 20 can pivot between an open position (FIG. 1) and a closed position (FIG. 11). In embodiments, the cartridge assembly 36 includes a channel 44 (FIG. 2) that defines a longitudinal slot 46 and a staple cartridge 48 having a tissue contact surface 50. The staple cartridge 48 defines a plurality of staple pockets 52 and is received within the longitudinal slot 46 of the channel 44. In some embodiments, the staple cartridge 48 is adapted to be released from the channel 44 after firing of the tool assembly 20 and replaced with a new or loaded staple cartridge 48. Each of the staple pockets 52 is configured and dimensioned to receive a staple 54. In embodiments, the staple cartridge 48 has a tissue guide portion 56 that is angled away from the anvil 34 in the distal direction.

The anvil 34 defines a tissue engaging surface 58 and includes a distal end portion 34 b that is angled from the tissue engaging surface 58 of the anvil 34 towards the cartridge assembly 36 at an obtuse angle. The angled distal end portion 34 b of the anvil 34 forms a dissecting tip 60. In embodiments, the dissecting tip 60 is spaced from the tissue guide portion 56 of the staple cartridge 48 when the tool assembly 20 is in the clamped position and extends along an axis that is substantially parallel to an axis defined by the tissue guide portion 56. Alternately, the dissecting tip 60 may have other configurations.

With reference to FIGS. 2 and 6-10, the distal end portion 34 b of the anvil 34 defines a first slot 62 and a second slot 64 (FIG. 13) in respective first and second lateral sides 66 a, 66 b of the anvil 34. Since the first and second slots 62, 64 are configured the same or similarly, only the first slot 62 will be described in detail. The first slot 62 may be formed as a cutout in the first lateral side 66 a of the anvil 34 and has a transverse opening 68 (FIG. 7) oriented toward the cartridge assembly 36, and a longitudinal section 70 in communication with the transverse opening 68. The first lateral side 66 a of the anvil 34 has a support ledge 72 that partially defines the longitudinal section 70 of the first slot 62.

The cartridge assembly 36 further includes a locking member 74 positioned in a groove 76 (FIG. 9) defined in an outer surface of the channel 44 of the cartridge assembly 36 and is slidable therein along the longitudinal axis of the cartridge assembly 36. The locking member 74 includes an elongate element 78 and a pair of first and second latch arms 80, 82 protruding perpendicularly from a distal end portion 78 b of the elongate element 78. The elongate element 78 has a proximal end portion 78 a configured to be coupled to the clamping member 30. In particular, the proximal end portion 78 a of the elongate element 78 has an appendage 84 defining an opening 86 therein configured for removable receipt of a portion of the clamping member 30, as will be described.

As best shown in FIG. 10, the clamping member 30 has a latch member 88 extending distally from a bottom end portion thereof. The latch member 88 of the clamping member 30 has a protrusion 90 extending downwardly therefrom and configured for removable receipt in the opening 86 in the locking member 74 when the tool assembly 20 is in the closed configuration, such that advancement of the clamping member 30 causes advancement of the locking member 74.

The first and second latch arms 80, 82 of the locking member 74 extend around the outer surface of the channel 44 of the cartridge assembly 36 and are respectively disposed on opposite lateral sides of the cartridge assembly 36. Each of the first and second latch arms 80, 82 has a hook-shaped extension 92, 94 protruding inwardly. The extension 92, 94 of the first and second latch arms 80, 82 are configured for receipt in the respective first and second slots 62, 64 of the anvil 34 upon the tool assembly 20 moving to the closed position. The extension 92, 94 of the first and second latch arms 80, 82 are configured to cooperatively grasp the anvil 34 therebetween to prevent the anvil 34 and cartridge assembly 36 from separating from the closed position.

In operation, when the staple reload 10 is operably engaged to a handle assembly (not shown) of a surgical stapling device or a robotic surgical system, the staple reload 10 is actuated to move the tool assembly 20 from the open position (FIG. 1) to the closed position (FIG. 11) about tissue. The first firing shaft 24 of the drive assembly 22 translates distally while carrying the second firing shaft 28 therewith. Since the clamping member 30 is coupled to the second firing shaft 28, the clamping member 30 advances into engagement with cam surfaces 44 a, 44 b (FIGS. 9 and 12) on the channel 44 and/or the anvil 34. The clamping member 30 is advanced a predetermined distance to move the tool assembly 20 to the closed position.

As the anvil 34 and cartridge assembly 36 approximate, the extension 92, 94 of the first and second latch arms 80, 82 of the locking member 74 enter the respective first and second slots 62, 64 of the anvil 34 via the entry opening 68 of the slots 62, 64. At this stage, the locking member 74 is not yet preventing the tool assembly 20 from opening. Upon traveling the predetermined distance to close the tool assembly 20, the clamping member 30 abuts the proximal end portion 78 a of the elongate element 78 of the locking member 74 (FIG. 12). In addition, upon closing the tool assembly 20, the protrusion 90 (FIG. 10) of the clamping member 30 enters the opening 86 in the elongate element 78 of the locking member 74. Accordingly, further advancement of the clamping member 30 causes the locking member 74 to advance from a proximal position to a distal position.

In the proximal position, as shown in FIG. 11, the extensions 92, 94 (FIG. 10) of the first and second latch arms 80, 82 of the locking member 74 are disposed proximally of the support ledges 72 of the anvil 34. As the locking member 74 moves to the distal position, the extensions 92, 94 of the first and second latch arms 80, 82 of the locking member 74 traverse the longitudinal section 70 of the first and second slots 62, 64 and engage the support ledges 72, as shown in FIGS. 13 and 14. When the first and second latch arms 80, 82 engage the support ledges 72 of the anvil 34, opening of the anvil 34 and cartridge assembly 36 is resisted, thereby setting a gap distance between the anvil 34 and cartridge assembly 36.

After the clamping member 30 advances the locking member 74 to the distal, locking position, the clamping member 30 is stopped from further advancing to the tissue-contacting surfaces/through the staple cartridge 44 of the tool assembly 20 by a distal limit of the slot 32 (FIG. 2) defined in the anvil 34. As described above, the second firing shaft 28 disengages the first firing shaft 24, allowing the first firing shaft 24 and the sled 26 to advance through the staple cartridge 48 independently of the clamping member 30 to eject staples from the staple cartridge 48.

After the sled 26 traverses to the distal end portion 36 b of the cartridge assembly 36, the sled 26 may be retracted by retracting the first firing shaft 24. As the first firing shaft 24 retracts, the sled 26 engages the clamping member 30, whereby the clamping member 30 is moved proximally. Since the protrusion 90 of the clamping member 30 is received in the opening 86 in the elongate element 78 of the locking member 74, retraction of the clamping member 30 drives a retraction of the locking member 74. As the locking member 74 retracts, the first and second latch arms 80, 82 moves proximally within the respective first and second slots 62, 64 of the anvil 34 to disengage the extension 92, 94 of the first and second latch arms 80, 82 from the support ledge 72 of the anvil 34. With the locking member 74 of the cartridge assembly 36 out of locking engagement with the anvil 34, the tool assembly 20 is no longer prevented from moving out of the closed position.

FIGS. 15-22 illustrate another embodiment of a locking member 174 for setting the tissue gap of a tool assembly 120. The tool assembly 120 is similar to tool assembly 20 and will only be described in detail to describe differences between the two assemblies.

The tool assembly 120 includes an anvil 134 and a cartridge assembly 136 movably coupled to one another. The anvil 134 defines a slot 162 that extends through the distal end portion 134 b thereof. The distal end portion 134 b of the anvil 134 has a support ledge 172 that partially defines the slot 162. The cartridge assembly 136 includes a clamping member 130 disposed at the proximal end portion 136 a thereof, a locking member 174 disposed at the distal end portion 136 b thereof, and an elongated locking plate 178 interconnecting the clamping member 130 and the locking member 174.

The locking plate 178 is slidably coupled to the cartridge assembly 136 and defines a proximal slot 190 in a proximal end portion 178 a of the elongate plate 178, and a distal slot 192 in a distal end portion 178 b of the elongate plate 178. The clamping member 130 is received in the proximal slot 190 and the locking member 174 is received in the distal slot 192. The clamping member 130 is captured within the proximal slot 190 of the locking plate 178, such that translation of the clamping member 130 results in translation of the locking plate 178. The locking member 174 may be shaped as an I-beam having a bottom end portion 174 a received in the distal slot 192 of the elongate plate 178, and a top end portion 174 b configured for receipt in the slot 162 of the anvil 134. The distal slot 192 of the elongate locking plate 178 is sized to allow for relative movement between the locking plate 178 and the bottom end portion 174 a of the locking member 174.

In operation, the clamping member 130 is advanced from a proximal position, as shown in FIG. 15, to a first distal position, as shown in FIG. 17, to move the tool assembly 120 from the open position to the closed position. As the clamping member 130 moves to the first, distal position, the locking plate 178 moves with the clamping member 130 a predetermined distance. Since the distal slot 192 is longer than the bottom end portion 174 a of the locking member 174 (FIG. 16), the initial distal translation of the elongate plate 178 during closing of the tool assembly 120 does not result in translation of the locking member 174.

Upon closing the tool assembly 120, as shown in FIG. 18, the top end portion 174 b of the locking member 174 is received in the slot 162 in the anvil 134. In this position, the anvil 134 and cartridge assembly 136 remain separable from one another. The clamping member 130 is further advanced, thereby advancing the elongate plate 178 into engagement with the bottom end portion 174 a of the locking member 174, as shown in FIGS. 18 and 19. With the elongate plate 178 abutting the bottom end portion 174 a of the locking member 174, further advancement of the elongate plate 178 via the advancing clamping member 130 drives the locking member 174 distally, whereby the top end portion 174 b of the locking member 174 traverses the slot 162 in the anvil 134 and engages the support ledge 172, as shown in FIG. 20. With the top end portion 174 b of the locking member 174 disposed on the support ledge 172 of the anvil 134 and the bottom end portion 174 a of the locking member 174 disposed on the elongate plate 178 of the cartridge assembly 136, separation of the tool assembly 120 out of the closed position is resisted.

With reference to FIGS. 21 and 22, to allow for separation of the anvil 134 and cartridge assembly 136 from one another, the clamping member 130 is retracted, whereby the elongate plate 178 ultimately engages the bottom end portion 174 a of the locking member 174. Further retraction of the elongate plate 178, via the clamping member 130, proximally translates the locking member 174 relative to the anvil 134 to disengage the top end portion 174 b of the locking member 174 from the support ledge 172 of the anvil 134. With the locking member 174 disengaged from the anvil 134, further retraction of the clamping member 130 moves the tool assembly 120 from the closed position to the open position.

FIGS. 23-26 illustrate another embodiment of a locking member 260 for setting the tissue gap of a tool assembly 220. The tool assembly 220 is similar to tool assembly 20 and will only be described in detail to describe differences between the two assemblies.

The tool assembly 220 includes an anvil 234 and a cartridge assembly 236 movably coupled to one another. The anvil 234 defines a slot 262 that extends through a distal end portion 234 b thereof. The distal end portion 234 b of the anvil 234 has a cam surface 270 leading to a support ledge 272 that together partially define the slot 262. The cam surface 270 is angled proximally so that the support ledge 272 overhangs an entry opening 268 of the slot 262.

The cartridge assembly includes a locking member 274 pivotably supported in the distal end portion 236 b of the cartridge assembly 236. The cartridge assembly 236 includes a biasing member 278 (e.g., a torsion spring) coupled to a bottom end portion 274 a of the locking member 274 and an engagement surface 280 of the cartridge assembly 236. The biasing member 278 is configured to resiliently bias the locking member 274 toward a locking position, in which the locking member 274 is perpendicular to a longitudinal axis defined by the cartridge assembly 236. The locking member 274 includes a top end portion 274 b having an extension 290 configured to be supported on the support ledge 272 of the anvil 234 to prevent the anvil 234 and cartridge assembly 236 from moving out of the closed position. The tool assembly 220 further includes a sled 226 (FIGS. 25 and 26), similar to the sled 26 described above, slidably supported in the cartridge assembly 236 for ejecting staples from the cartridge assembly 236.

In operation, as the tool assembly 220 moves from the open position, as shown in FIG. 23, toward a partially closed position, as shown in FIG. 24, the top end portion 274 a of the locking member 274 engages the cam surface 270 of the anvil 234. The cam surface 270 pivots the locking member 274 out of the locking position, in the direction indicated by arrow “A” in FIG. 24, against the bias of the biasing member 278. As the anvil 234 and cartridge assembly 236 move toward the fully closed position, as shown in FIG. 25, the protrusion 290 of the locking member 274 passes further into the slot 262 of the anvil 234 and passed the support ledge 272. The biasing member 278 pivots the locking member 274 about the bottom end portion 274 a thereof, in the direction indicated by arrow “B” in FIG. 25, to engage the protrusion 290 of the locking member 274 with the support ledge 272 of the anvil 234. In this position, the locking member 274 resists separation of the anvil 234 and cartridge assembly 236 from one another.

With reference to FIGS. 25 and 26, the sled 226 advances through the cartridge assembly 236 until it ejects all of the staples in the distal end portion 236 b of the cartridge assembly 236, whereupon the sled 226 engages the bottom end portion 274 a of the locking member 274. The locking member 274 rotates in the direction indicated by arrow “A” out of the locking position to disengage the protrusion 290 of the locking member 274 from the support ledge 272 of the anvil 234. With the locking member 274 disengaged from the support ledge 272 of the anvil 234, movement of the anvil 234 and cartridge assembly 236 out of the closed position is permitted.

While the tool assemblies described herein are shown in the drawings as linear tool assemblies, it is contemplated that the tool assemblies may be configured as curved tool assemblies with similar components and methods of operation.

Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments. It is envisioned that the elements and features illustrated or described in connection with one exemplary embodiment may be combined with the elements and features of another without departing from the scope of this disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described embodiments. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. 

1-20. (canceled)
 21. A tool assembly comprising: an anvil having a proximal portion and a distal portion, the distal portion of the anvil defining a slot therein; a cartridge assembly having a proximal portion and a distal portion, the proximal portion of the cartridge assembly movably coupled to the proximal portion of the anvil such that the anvil and cartridge assembly are transitionable between an open position and a closed position; and a locking member movably supported on the distal portion of the cartridge assembly, wherein the locking member is configured to move into locking engagement with the slot as the anvil and cartridge assembly transition toward the closed position to set a gap distance between the anvil and cartridge assembly.
 22. The tool assembly according to claim 21, further comprising a biasing member coupled to the locking member for resiliently biasing the locking member into locking engagement with the slot.
 23. The tool assembly according to claim 21, wherein the distal portion of the anvil has a cam surface and a support ledge, the cam surface being configured to move the locking member as the anvil and cartridge assembly transition toward the closed position.
 24. The tool assembly according to claim 23, further comprising a biasing member coupled to the locking member, wherein the biasing member is configured to pivot the locking member onto the support ledge when the anvil and the cartridge assembly transition to the closed position.
 25. The tool assembly according to claim 23, wherein the locking member includes: a top end portion including an extension configured to be supported on the support ledge of the anvil to prevent the anvil and cartridge assembly from moving out of the closed position; and a bottom end portion supported in the cartridge assembly.
 26. The tool assembly according to claim 25, wherein the bottom end portion of the locking member is pivotably supported by the cartridge assembly.
 27. The tool assembly according to claim 21, wherein the locking member is configured to pivot relative to the cartridge assembly into locking engagement with the slot in response to the anvil and cartridge assembly transitioning toward the closed position.
 28. The tool assembly according to claim 27, further comprising a sled slidably supported in the cartridge assembly and configured to eject staples from the cartridge assembly, wherein the sled is configured to engage the locking member to pivot the locking member out of locking engagement with the slot after the anvil and cartridge assembly transition to the closed position.
 29. The tool assembly according to claim 21, wherein the locking member is perpendicular relative to a longitudinal axis defined by the cartridge assembly.
 30. A tool assembly comprising: an anvil having a proximal portion and a distal portion, the distal portion of the anvil defining a slot therein; a cartridge assembly having a proximal portion and a distal portion, the proximal portion of the cartridge assembly movably coupled to the proximal portion of the anvil such that the anvil and cartridge assembly are transitionable between an open position and a closed position; a locking member including: a bottom end portion pivotably supported by the distal portion of the cartridge assembly; and a top end portion configured for locking engagement with the slot of the anvil to set a gap distance between the anvil and cartridge assembly when the anvil and cartridge assembly are in the closed position; and a sled slidably supported in the cartridge assembly and configured to eject staples from the cartridge assembly, wherein the sled is configured to engage the locking member to pivot the locking member out of locking engagement with the slot after the anvil and cartridge assembly transition to the closed position.
 31. The tool assembly according to claim 30, further comprising a biasing member coupled to the locking member for resiliently biasing the locking member into locking engagement with the slot of the anvil.
 32. The tool assembly according to claim 31, wherein the distal portion of the anvil has a cam surface and a support ledge, the cam surface being configured to pivot the locking member against the resilient bias of the biasing member as the anvil and cartridge assembly transition toward the closed position.
 33. The tool assembly according to claim 32, wherein the biasing member is configured to move the top end portion of the locking member onto the support ledge when the anvil and cartridge assembly transition to the closed position.
 34. The tool assembly according to claim 33, wherein the top end portion of the locking member has a lateral extension configured to be supported on the support ledge of the anvil to prevent the anvil and cartridge assembly from moving out of the closed position.
 35. The tool assembly according to claim 30, wherein the locking member is perpendicular relative to a longitudinal axis defined by the cartridge assembly. 